1. Field of the Invention
The present invention relates to medical treatment of varicose veins, and more particularly, to a minimally invasive method and apparatus for treating varicose veins that allows for complete obliteration of the affected veins without scarring or any of the other undesirable complications of conventional treatments.
2. Description of Related Art
Varicose veins is a medical condition present in up to twenty-five percent of the adult population, and is especially prevalent among middle-aged women. The term "varicose" is derived from the Greek word for "grape-like" and refers to the torturous appearance of the afflicted veins. Patients suffering from varicose veins often experience various symptoms, including aching, itching, heaviness, swelling or cramping of the legs, while more serious complications of varicose veins can include thrombophlebitis, dermatitis, hemorrhage and ulcers. Even absent such complications, many patients seek medical treatment of varicose veins for primarily cosmetic reasons due to the generally unsightly appearance that characterizes the condition.
Specifically, varicose veins are a condition of the superficial veins of the legs in which the veins have become abnormally twisted, lengthened, or dilated. The condition is usually caused by inefficient or defective one-way valves within the veins. These one-way valves provide an important function in controlling blood pressure within the venous system of the legs. During walking, the leg muscles provide a musculovenous pump that compresses the veins and propels blood to the heart. Efficiency of the musculovenous pump is enhanced by the one-way valves within the veins that protect the venous system at the lower extremities from excess pressure generated by coughing, straining, lifting, standing or other such exertion. The superficial veins normally carry only ten to fifteen percent of the blood, with the remainder carried by the deep veins; however, the percentage of blood carried by the superficial veins can exceed these normal levels due to dilation of the superficial veins or thrombosis of the deep veins. As a result, the one-way valves can become incompetent which further increases retrograde pressure within the superficial veins. Since the superficial veins lie close to the skin layer and are poorly supported by the subcutaneous tissue, the increased retrograde pressure causes the varicose veins to be formed.
There are two known types of treatment for varicose veins. A first type of treatment comprises surgical removal of the superficial varicose veins, also referred to as "vein stripping." In the stripping technique, a surgeon first makes an incision at the groin area through which the saphenous vein is separated from the femoral vein. The saphenous vein is also dissected at the foot, and at that point, a vein stripper, such as a wire, is inserted into the lumen of the saphenous vein. The wire is then threaded through the saphenous vein to the incision at the groin. The wire includes a nut at an end thereof that catches on the foot end of the saphenous vein. The surgeon then removes the wire though the groin incision to gently extract the vein. It is further necessary to make multiple small incisions along the leg in order to disconnect the numerous tributary veins from the saphenous vein and to ligate these tributary veins. Once the saphenous vein is completely removed from the leg, the various incision wounds can be sutured closed.
The stripping technique represents a permanent solution in that the varicose vein condition cannot recur once the vein has been removed. Nevertheless, the technique has numerous significant drawbacks that render it an unsatisfactory treatment. The numerous incisions often leave substantial unsightly scars along the legs that can be as unpleasant in appearance as the original varicose vein condition. Moreover, the procedure is generally performed under general anesthesia and often requires an overnight hospital stay. There are also associated complications of the technique, such as blood loss, pain, infection, hematoma, nerve injury and swelling. After undergoing the stripping technique, a patient generally requires several weeks to recover. In view of these significant drawbacks, the stripping technique is recommended only for extreme cases of varicose veins, and for patients that are in sufficiently good health to handle the surgery.
A second technique for treating varicose veins is known as sclerotherapy. This technique involves injection of toxic fluids, such as sodium tetradecyl sulfate, into the veins to cause subsequent inflammation and sclerosis of the veins. The sclerosis results in localized scarring or closure of the veins, which forces rerouting of the blood away from the affected veins. The sclerotherapy technique is often combined with an operative procedure, such as ligation of a portion of the saphenous vein.
While the sclerotherapy technique is less surgically intensive than the stripping technique, it often does not represent a permanent or complete solution since it has a high rate of recurrence and cannot be applied to the saphenous vein in the upper thigh region due to the risk of sclerosis of the deep veins. Sclerotherapy has other potentially serious complications, including skin staining, ulceration, phlebitis, allergic or anaphylactic overdose, ischemia, skin or fat necrosis, and peripheral neuropathy. Notwithstanding these complications, patients must often undergo multiple courses of sclerotherapy treatment in order to completely alleviate the varicose veins to a satisfactory degree.
In view of these significant drawbacks of the conventional treatments for varicose veins, a critical need exists for a minimally invasive and permanent treatment for varicose veins. Such a treatment should provide for complete obliteration of the affected veins without visible scarring, excess hospitalization or any of the other undesirable complications of the conventional treatments.